CHIP8 thread - Page 4

dreampeppers99 · January 14th, 2009

Quote:

Originally Posted by Shendo

Cool emu dreampeppers99.

Thanks

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**ShendoXT** · January 14th, 2009

Quote:

Originally Posted by runawayprisoner

You will also see this in Pong when you move your paddle past the top and bottom of the screen..

Actually pong is programmed to wrap paddles around (though it needs to completly disappear from the screen to appear on the other side).

Quote:

Originally Posted by runawayprisoner

Also among the undocumented features is that for subtraction, when the result is zero or lower, the flag is set. It's not a carry flag there, it's a carry and zero flag. Cowgod didn't state it so in his document, and neither did David Winter.

Nice find. Explains why Ant doesn't work properly on my emu.

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dreampeppers99 · January 14th, 2009

Quote:

Originally Posted by Shendo

Nice find. Explains why Ant doesn't work properly on my emu.

in my too

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dreampeppers99 · January 17th, 2009

The source code from JChip8BR is on svn google's.
jchip8br - Google Code
The code is not so beautiful and faster but I hope you can take some acknoledges.

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runawayprisoner · January 17th, 2009

Quote:

Originally Posted by Shendo

Actually pong is programmed to wrap paddles around (though it needs to completly disappear from the screen to appear on the other side).

Ah... yep. Just checked the source code again, and it seems the game has its own check. But anyway, try Tank. That game doesn't seem to work right (or at all) if you don't wrap the sprite around to the other side of the screen.

Quote:

Nice find. Explains why Ant doesn't work properly on my emu.

Yeah... it boggled my mind for quite a while. It didn't look like anything was wrong, and indeed nothing was wrong except for the flag.

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cChip interpreter WIP - current status: Release Candidate
LRx Filter RC - current performance rating: 9/10

Dax · February 27th, 2009

Once I get a bit more free time, I think I'm going to rewrite my emulator from scratch in proper C++/SDL[it was a horrible mix of C/C++ before]. Yeah, I didn't finish it the first time, but it was crappy anyway. Really hacky and too much guesswork involved, and worst of all, I didn't hardly document it. I'm going to try and brush up on bit logic and such a bit more this time. It's still confusing to me.

If you want to see my crappy source of it: http://code.google.com/p/chip8-emu/ It's under the BSD license[I'm so lazy I never even copy pasted the license in the code xD], do what you want with it, just remember who wrote it.

It never had graphics or anything. It was a CLI app since I wanted to do graphics last.

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Last edited by Dax; February 27th, 2009 at 09:39..

runawayprisoner · February 27th, 2009

I kinda think it's better to include your opcode interpreter into the main opcode table to avoid function calls, and possibly improve a bit of performance. Though indeed it's a bit harder to manage that way.

(to be honest, I split them into functions with my Gameboy emulator, anyway)

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LRx Filter RC - current performance rating: 9/10

Dax · February 27th, 2009

Isn't the code really ugly?

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runawayprisoner · February 27th, 2009

You haven't seen ugly yet.

Ugly is 30 different files, headers and definitions, in separate folders, each with over 5000 lines of codes. ;p

You're doing fine.

As for optimization practices, no comment. The more you work on something, the better you are at optimizing for it.

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Dax · February 27th, 2009

Thanks. I personally thought the code was ugly..

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runawayprisoner · February 27th, 2009

Well, you can stick a flower in it to make it look pretty then.

Sufficient codes are not always pretty, though. And some "deprecated" stuffs might still be faster and more efficient than the "new" stuffs. But they're still "deprecated" because they're harder to use and maintain. Hmm... as is the case with ActionScript and Java.

Fun note: ActionScript 3.0 should be Action language instead of an "Action" script, but I think it'd just sound stupid as Action... and they stuck "script" in the back of it in the end.

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LRx Filter RC - current performance rating: 9/10

Dax · February 27th, 2009

I know not all code is pretty, but there're usually better ways of doing things.

Usually the same applies to my case/situation.

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runawayprisoner · February 27th, 2009

Whooel... for instance,

byte >> 3 & 1
byte >> 2 & 1
byte >> 1 & 1
byte & 1

...is definitely faster to fetch binary code than a look-up table that requires you to convert to hex before hand.

But hell... I wonder why people still do that sometimes... hmm...

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LRx Filter RC - current performance rating: 9/10

Dax · February 27th, 2009

I've never messed with lookup tables before.

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Dax · March 9th, 2009

The CHIP8 returneth! Hatori and I have been chatting on MSN tonight, and I'm going to clean up my code, and learn more about bitshifting again after my long absence. I want to make this thing a reality.

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jaskt7 · March 13th, 2009

Hi, I was wondering if somebody that knew actionscript could help me out on my CHIP8 emu. I have not tested many games on it, but I know for sure that a few work, however; it seems that Space Invaders' home screen is not working correctly.

The swf can be found here on this page, it automatically loads Space Invaders by default. The source code is also included below it.

chip

*the emu is not the fastest thing in the world, I am just trying to get it to work.

Thanks for any feedback I get.

jaskt7 · March 13th, 2009

Okay, I found the error. Apparently when I was loading the rom from the php script, I did not convert the "string number" into an "actual number" in Flash. Honestly, I do not even know why any game worked in the emu in the first place.

Strangely enough, I found this bug by displaying the hex values of the rom after it loaded...but it was not displaying hex, rather decimal. After a few head scratches I realized that the numbers were still strings.

**Chrono Archangel** · March 13th, 2009

did you update your link? I still see garbled text scrolling.

on a side note, I finally fix a few issues that was in my emu...
-it now runs semi-fullspeed (drawing the WHOLE screen everytime is just a bad idea... can't believe I made that mistake)
-added fonts
-fix outofbound errors when paddle would wrap in pong (offscreen drawing).

Screenshot!

Attached Images

chip8.jpg (180.6 KB, 12 views)

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jaskt7 · March 13th, 2009

No, I did not update the link last night, however; I did just put the new file up online.

You have a good idea not to draw the whole screen every time, I might implement that into my emu. But, first things first; I am probably going to convert it over to C++ in a couple of weeks (I cannot right now, too busy).

runawayprisoner · March 13th, 2009

Quote:

Originally Posted by jaskt7

Hi, I was wondering if somebody that knew actionscript could help me out on my CHIP8 emu. I have not tested many games on it, but I know for sure that a few work, however; it seems that Space Invaders' home screen is not working correctly.

Thanks for any feedback I get.

Space Invaders may suffer from wrong collision flag set... a whole lot. So pay attention to that one.

Also you should try to load the binary file directly into the URLLoader then convert it to a ByteArray instead of waiting for php to pass it to you. That's quite messy imo.

Unless, of course, you are using ActionScript 2. Which then makes this an even more troublesome experience. Not that it's impossible but it's just quite difficult.

Quote:

Originally Posted by Chrono Archangel

did you update your link? I still see garbled text scrolling.

on a side note, I finally fix a few issues that was in my emu...
-it now runs semi-fullspeed (drawing the WHOLE screen everytime is just a bad idea... can't believe I made that mistake)
-added fonts
-fix outofbound errors when paddle would wrap in pong (offscreen drawing).

Screenshot!

Looking good.

Do Super Chip games work?

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cChip interpreter WIP - current status: Release Candidate
LRx Filter RC - current performance rating: 9/10

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January 17th, 2009	#64 (permalink)
dreampeppers99 Registered User Join Date: Jul 2006 Location: you know... Posts: 506	The source code from JChip8BR is on svn google's. jchip8br - Google Code The code is not so beautiful and faster but I hope you can take some acknoledges. __________________ The Empyrean

February 27th, 2009	#66 (permalink)
Dax ライチュウ Join Date: Nov 2006 Location: USA Posts: 3,289	Once I get a bit more free time, I think I'm going to rewrite my emulator from scratch in proper C++/SDL[it was a horrible mix of C/C++ before]. Yeah, I didn't finish it the first time, but it was crappy anyway. Really hacky and too much guesswork involved, and worst of all, I didn't hardly document it. I'm going to try and brush up on bit logic and such a bit more this time. It's still confusing to me. If you want to see my crappy source of it: http://code.google.com/p/chip8-emu/ It's under the BSD license[I'm so lazy I never even copy pasted the license in the code xD], do what you want with it, just remember who wrote it. It never had graphics or anything. It was a CLI app since I wanted to do graphics last. __________________ My PC Specs\|My Consoles\|Emu SVNs\|Project OSX\|How to ask a Question Last edited by Dax; February 27th, 2009 at 09:39..

February 27th, 2009	#67 (permalink)
runawayprisoner Mobile Fanatic Join Date: Nov 2006 Location: Santa Cruz, CA Posts: 6,205	I kinda think it's better to include your opcode interpreter into the main opcode table to avoid function calls, and possibly improve a bit of performance. Though indeed it's a bit harder to manage that way. (to be honest, I split them into functions with my Gameboy emulator, anyway) __________________ cChip interpreter WIP - current status: Release Candidate LRx Filter RC - current performance rating: 9/10

February 27th, 2009	#68 (permalink)
Dax ライチュウ Join Date: Nov 2006 Location: USA Posts: 3,289	Isn't the code really ugly? __________________ My PC Specs\|My Consoles\|Emu SVNs\|Project OSX\|How to ask a Question

February 27th, 2009	#69 (permalink)
runawayprisoner Mobile Fanatic Join Date: Nov 2006 Location: Santa Cruz, CA Posts: 6,205	You haven't seen ugly yet. Ugly is 30 different files, headers and definitions, in separate folders, each with over 5000 lines of codes. ;p You're doing fine. As for optimization practices, no comment. The more you work on something, the better you are at optimizing for it. __________________ cChip interpreter WIP - current status: Release Candidate LRx Filter RC - current performance rating: 9/10

February 27th, 2009	#70 (permalink)
Dax ライチュウ Join Date: Nov 2006 Location: USA Posts: 3,289	Thanks. I personally thought the code was ugly.. __________________ My PC Specs\|My Consoles\|Emu SVNs\|Project OSX\|How to ask a Question

February 27th, 2009	#71 (permalink)
runawayprisoner Mobile Fanatic Join Date: Nov 2006 Location: Santa Cruz, CA Posts: 6,205	Well, you can stick a flower in it to make it look pretty then. Sufficient codes are not always pretty, though. And some "deprecated" stuffs might still be faster and more efficient than the "new" stuffs. But they're still "deprecated" because they're harder to use and maintain. Hmm... as is the case with ActionScript and Java. Fun note: ActionScript 3.0 should be Action language instead of an "Action" script, but I think it'd just sound stupid as Action... and they stuck "script" in the back of it in the end. __________________ cChip interpreter WIP - current status: Release Candidate LRx Filter RC - current performance rating: 9/10

February 27th, 2009	#72 (permalink)
Dax ライチュウ Join Date: Nov 2006 Location: USA Posts: 3,289	I know not all code is pretty, but there're usually better ways of doing things. Usually the same applies to my case/situation. __________________ My PC Specs\|My Consoles\|Emu SVNs\|Project OSX\|How to ask a Question

February 27th, 2009	#73 (permalink)
runawayprisoner Mobile Fanatic Join Date: Nov 2006 Location: Santa Cruz, CA Posts: 6,205	Whooel... for instance, byte >> 3 & 1 byte >> 2 & 1 byte >> 1 & 1 byte & 1 ...is definitely faster to fetch binary code than a look-up table that requires you to convert to hex before hand. But hell... I wonder why people still do that sometimes... hmm... __________________ cChip interpreter WIP - current status: Release Candidate LRx Filter RC - current performance rating: 9/10

February 27th, 2009	#74 (permalink)
Dax ライチュウ Join Date: Nov 2006 Location: USA Posts: 3,289	I've never messed with lookup tables before. __________________ My PC Specs\|My Consoles\|Emu SVNs\|Project OSX\|How to ask a Question

March 9th, 2009	#75 (permalink)
Dax ライチュウ Join Date: Nov 2006 Location: USA Posts: 3,289	The CHIP8 returneth! Hatori and I have been chatting on MSN tonight, and I'm going to clean up my code, and learn more about bitshifting again after my long absence. I want to make this thing a reality. __________________ My PC Specs\|My Consoles\|Emu SVNs\|Project OSX\|How to ask a Question

March 13th, 2009	#76 (permalink)
jaskt7 Registered User Join Date: Mar 2009 Location: United States Posts: 9	Hi, I was wondering if somebody that knew actionscript could help me out on my CHIP8 emu. I have not tested many games on it, but I know for sure that a few work, however; it seems that Space Invaders' home screen is not working correctly. The swf can be found here on this page, it automatically loads Space Invaders by default. The source code is also included below it. chip *the emu is not the fastest thing in the world, I am just trying to get it to work. Thanks for any feedback I get.

March 13th, 2009	#77 (permalink)
jaskt7 Registered User Join Date: Mar 2009 Location: United States Posts: 9	Okay, I found the error. Apparently when I was loading the rom from the php script, I did not convert the "string number" into an "actual number" in Flash. Honestly, I do not even know why any game worked in the emu in the first place. Strangely enough, I found this bug by displaying the hex values of the rom after it loaded...but it was not displaying hex, rather decimal. After a few head scratches I realized that the numbers were still strings.

March 13th, 2009	#79 (permalink)
jaskt7 Registered User Join Date: Mar 2009 Location: United States Posts: 9	No, I did not update the link last night, however; I did just put the new file up online. You have a good idea not to draw the whole screen every time, I might implement that into my emu. But, first things first; I am probably going to convert it over to C++ in a couple of weeks (I cannot right now, too busy).